Japan-Germany Gemstone Research Institute

[Deadline: Wed, Sept 22 at 10 AM: Lottery Sale_09] Parasitic Peridot 0.536ct Loose Stone, NGL Certified Sale price¥228,000

Brazilian Bicolor Pink Euclase 0.236ct Loose Stone, Japan-Germany Sale price¥110,000

Madagascar Datolite (Datolite) 0.919ct Loose Stone Japan-Germany Exchange Sale price¥69,800

[Item 12564407] Stibiotantalite from Afghanistan, 0.200ct loose stone Sale price¥45,800

[Item 12564406] Stibiotantalite from Afghanistan, 0.186ct loose stone Sale price¥45,800

Pt900 ピンクサファイア 0.42ct ダイヤモンド 0.05ctリング日独鑑

[Item 22602811] [Coloriful] Pt900 Pink Sapphire 0.42ct Diamond 0.05ct Ring with Appraisal Report Sale price¥59,800

[Deadline 8/29 | Lottery Sale] Brazilian Indicolite Tourmaline 2.587ct Loose Stone, with NGL Certificate Sale price¥98,000

[9/25 10 PM Release] Indonesian Parasitic Peridot 3.8mm/0.268ct Loose Gemstone, NGL Certified Sale price¥128,000

【Lottery Sale_11】【For Winners Only】【Item 12560839】 Indonesian Parasitic Peridot 0.262ct Loose Stone, GGL Certified Sale price¥98,000

Namibian Dioptase 0.134ct Loose Stone, Japan-Germany Mirror Sale price¥49,800

[Available 9/14, 10 PM] Stibiotantalite from Afghanistan, 0.212ct loose stone, JGL certified Sale price¥39,800

【Lottery Sale ②_202608_12】Brazilian Bi-Color Pink Euclase 3.210ct Loose Stone with Japan-Germany Gemological Report Sale price¥798,000

Cassiterite 1.658ct loose stone (bicolor cassiterite) Japan-Germany exchange Sale price¥98,000

Manganotantalite 0.736ct loose stone from Japan and Germany Sale price¥128,000

Lottery Sale 0812_15: Brazilian Indicolite Tourmaline 3.756ct Loose Stone with Japan-Germany Gemological Report Sale price¥98,000

Brazilian Dolomite 4.070ct Loose Stone, Japan-Germany Mirror Sale price¥79,800

Brazilian Yellow Beryl 11.411ct Loose Stone, Japan-Germany Exchange Sale price¥25,800

Brazilian Indigolite Tourmaline 1.514ct Loose Stone, Japan-Germany Exchange Sale price¥55,800

[Lottery Sale 0731_06] Colombian Pyrite in Emerald 2.988 ct Loose Stone with Japanese and German Gemological Certificates Sale price¥228,000

Pakistani Clinohumite 1.440ct Loose Stone, Japan-Germany Exchange Sale price¥39,800

Purple zoisite from Tanzania 1.103ct loose Japanese German edition Sale price¥98,000

[On sale 8/23 at 10 PM JST] Sri Lankan Yellow Sapphire 1.100ct Loose Stone, Japan/Germany certified Sale price¥49,800

【Lottery Sale 0731_08】Brazilian Emerald Cat's Eye 6.083ct Loose Gemstone with Japanese and German Gemological Report Sale price¥258,000

[#202607AkihabaraPopUpTakenOut] [12560302Listed] Magnesioaxinite 0.154ct Loose Sale price¥18,800

[Listed as 12562727] Pink Imperial Topaz 1.907ct Loose Stone Sale price¥118,000

[On sale August 8th, 10 PM JST] Mexican Cantera Opal 6.357ct Loose Stone (Impregnated) with Japan-Germany Gemological Report Sale price¥18,800

[On sale August 8th, 10 PM JST] Mexican Cantera Opal 5.079 ct Loose Stone (Filled) with Japan-Germany Gemstone Appraisal Sale price¥25,800

2.251ct Loose Brazilian Amphibole in Danburite with Japan-Germany Gemological Report Sale price¥29,800

Sri Lankan cobalt spinel 0.281ct loose stone Sale price¥55,800

Blue Sapphire 0.369ct Loose Gemstone with Japan-Germany Appraisal Sale price¥22,800

[12552038] Beryl Cat's Eye 32.703ct Loose Stone Sale price¥98,000

[12552306] Iolite 14.158ct loose stone Sale price¥258,000

Scapolite 0.587ct loose stone from Japan and Germany Sale price¥8,800

Peruvian Gem Silica (Chrysocolla Chalcedony) 4.098 ct Loose, Japan-Germany certified Sale price¥24,800

Peruvian Gem Silica (Chrysocolla Chalcedony) 3.210ct Loose Stone, Japan-Germany certified Sale price¥19,800

Peruvian Gem Silica (Chrysocolla Chalcedony) 2.556ct Loose Stone with Japan-Germany Gemological Report Sale price¥15,800

Brazilian Indigolite Tourmaline 1.247ct Loose Stone, Japan-Germany Exchange Sale price¥98,000

Cerussite from Morocco, 1.026 ct, loose, with Japanese and German gemological reports Sale price¥69,800

Brazilian pink euclase 0.310 ct loose stone, with Japan-Germany gemological report Sale price¥98,000

0.904ct Datolite, USA (Westfield, Manchester) Loose, with Japan-Germany certification Sale price¥29,800

Natural Emerald from Brazil, 15.219 ct, Loose Stone, Nichidoku Identification Report Sale price¥398,000

Sri Lankan Topaz Cat's Eye 3.384ct Loose with Japanese-German gemological certificate Sale price¥12,800

Sri Lankan Colorless Enstatite 1.877 ct Loose with Japan-Germany Gemological Report Sale price¥29,800

2.567ct Enstatite from Sri Lanka, Loose Gemstone, Nichidoku Identification Sale price¥18,800

Tibetan Andesine 18.643ct Loose Stone, Japan & Germany Gemological Institute certified Sale price¥98,000

Dominican Republic Larimar, 33.829ct Loose Stone, Japan-Germany Gemological Report Sale price¥49,800

Afghanite 0.447ct loose stone from Afghanistan, Japan-Germany Sale price¥5,980

KARATZ Custom Made

Why not take your favorite gemstone that you found at KARATZ and have it made into custom-made jewelry? It will be made by skilled Japanese craftsmen.
We carefully craft each piece of jewelry, starting with the stone setting, to match the individual characteristics of the gemstone.

KARATZ・Five Commitments

So that more people can feel closer to jewellery and enjoy it easily.
We will introduce KARATZ's thoughts on products, the attention to detail and efforts in selecting gemstones and creating jewelry.

KARATZ's Initiatives and Social Contributions

We will introduce KARATZ's efforts, including nurturing the next generation and business collaboration to develop the industry, and supporting children in Sri Lanka, the land of jewels.

KARATZ Books

These are books that KARATZ has been involved in writing, supervising, and planning. They are all books that allow you to enjoy gemstones from various angles. You can also purchase them directly.

jeweler's tools

For those who want to enjoy jewelry more but don't know what tools to use, we will introduce tools that are also used by KARATZ staff. You can also purchase them directly.